I recently bought some very cheap DVD's, for that price they were obviously burned an re-sold. All of them played just fine when i first watched them, but then after about a week, my DVD player would not play the sound on any of them. Now it won't even play the sound on any of my good DVD's. I tried to reset my DVD player settings but this did not help. Is it the cheap DVD's that caused this? or did I reset something that I shouldn't have?

Audio is combined with the video and the laser reads that as a single data stream. If the audio quit, then that's a failure of the electronic part of the player or more likely just a wrong setting in the player. Make sure the output's not set to optical or coaxial if you are using just the stereo RCA output. Same with your audio amplifier. And as mentioned, a bad DVD wouldn't have much to do with it, unless it wore out the DVD mechanism from trying to read the discs. But then the video wouldn't work either.

Still, not a good idea to play back cheap discs because if they are really crappy they can make your player work much harder and that does generate heat and can cause increased wear on the drive mechanism and could lead to earlier failure.

my dvd player is connected to a kenwood audio video surround receiver krfv8030d vr409 n I control the volume from the receiver. but the receiver is also controlls volume for vcr n the vcr audio works just fine.